Photo-reduction assisted synthesis of MnO2/reduced graphene oxide/P25 for electrochemical detection of hydrogen peroxide

In this work, we report the synthesis of MnO2/RGO (reduced graphene oxide)/P25 nanocomposites for a non-enzymatic hydrogen peroxide sensor. MnO2/RGO/P25 nanocomposites were synthesized with a photo-reduction approach and characterized by field emission scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. A non-enzymatic hydrogen peroxide sensor was fabricated by dropping MnO2/RGO/P25 nanocomposites on the surface of a glassy carbon electrode. Electrochemical measurements of the MnO2/RGO/P25 modified electrode were carried out on an electrochemical workstation. The as-prepared sensor exhibited high electrocatalytic activity, selectivity and stability towards the oxidation of H2O2. Under optimum conditions, the calibration curve for H2O2 determination was linear in the range from 1.0 10-6 to 4.0 10-3 M (R2 = 0.999) with a detection limit of 3 10-7 M (S/N = 3).